1. Field of Technology
The present invention relates to a light emitting diode (LED) illumination/signal lamp, and, more particularly, to a LED illumination unit which is similar to, even better than, a conventional daylight lamp in fluorescent effect. The present invention further relates to the application of the fluorescence-like LED illumination unit.
2. Background
Compared with conventional illumination lamps, such as, incandescent lamps and daylight lamps, LED illumination lamps are characterized by long service life, high light efficiency, low power consumption, no fluorescent dye contamination, and so on, and are easily replaced. However, for existing LED lamp tubes for illumination, a circuit board and a LED array are disposed in the tube body of the lamp tube, LED illuminants are generally arranged in an axial direction of the tube body, and light emitting centers of the LED illuminants face a tube wall of the tube body. Such LED daylight lamps have problems such as, exposure of spotted light sources, small irradiation angle of the light path, string of bead-like LED spotted light sources forming the daylight lamp, dazzling light rays, significant difference from a light emitting mode of existing daylight lamps, and dizziness caused by multiple overlapping projections formed on the wall or ground by irradiating an irradiated object with multiple light spots. These LED daylight lamps fail to meet people's long-term use experience of conventional daylight lamps, have low comfortability, and thus are not suitable for domestic illumination.
To make the light emitting mode of the LED illumination lamps be close to that of the existing daylight lamps, many inventors are devoted to the research of the light emitting mode of the LED illumination lamps and produce many patents.
For example, a typical solution is to dispose two LED illuminants in opposite directions at two ends of an LED lamp tube and dispose a double-sided reflective sheet or light guide material or light reflecting material in the tube body, so that light emitted by the LED illuminants are reflected through the double-sided reflective sheet or the light reflecting material or scattered through the light guide material, so as to approximate the light emitting mode of the existing daylight lamps. Such a typical solution is, for example, an LED daylight lamp disclosed in Chinese Invention Patent Publication No. CN101144591A, an LED daylight lamp disclosed in Chinese Utility Model Patent Granted Publication No. CN200993322Y, or the like. However, such LED daylight lamps use a small number of LED illuminants with low illumination intensity, and thus are difficult to be used for daily illumination.
Another typical manner is to mix a certain amount of light scattering powder or light guide powder into the raw material of a PC or PV lamp tube uniformly during injection molding of the lamp tube and to form a hollow lamp tube by injection molding, so that light emitted by LED illuminants is transmitted through the PC or PV lamp tube. Such a patent is, for example, a soft LED daylight lamp with multiple light emitting angles disclosed in Chinese Utility Model Patent Granted Publication No. CN201293218Y. However, such an LED daylight lamp still can not solve the problems such as exposure of spotted light sources, large light path loss, and low illumination intensity in LED daylight lamps.
Still another typical manner is to use LED illuminants with lenses added therein, for example, a high-power LED daylight lamp disclosed in Chinese Utility Model Patent Granted Publication No. CN201330956Y. However, such an LED daylight lamp still can not solve the above relevant problems existing in LED daylight lamps well.